Дисертації: "Smart contact"

1

Miftah, el kheir Laila. "Smart devices for biomedical applications." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCD054.

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Dans cette thèse, nous nous sommes intéressés aux systèmes intelligents pour des applicationsmédicales et cosmétiques. Ainsi, nous avons conçu et réalisé trois instruments. Le premier estdédié à la mesure de la mouillabilité de la peau. L’originalité de ce dispositif réside en sa capacité àdonner une image 3D de la goûte de la surface de la peau explorée et de donner le comportementdynamique de la goûte. Cette stratégie nous donnera la possibilité de créer de nouvelles basesde données relatives à la mouillabilité de tout le corps humain. En effet, nous disposons que desdonnées sur la mouillabilité de l’avant-bras. Le deuxième instrument intelligent concerne la mesurede la réflectance d’une surface. Ce dispositif assure une mesure de très haute résolution angulairede la BRDF et une très bonne répétabilité de la mesure. Il a été validé sur la peau pour la mesurede l’ éclat. Et enfin le troisième instrument, basé sur une méthode originale de mesure de vibrationà l’aide d’un système de stéréo-vision associée à un motif périodique. Il a été appliqué pour lamesure du mouvement thoracique et abdominal lors de la respiration. Notre principale motivationpour développer ce système fut la réduction des artefacts, dus aux mouvements d’un patient lorsd’un examen radiologique
Smart Devices have been widely used by health care and cosmetics professionals. Indeed, they helpin many aspects of clinical practice by providing an efficient way for medical diagnosis, supportingbetter clinical decision-making and improving patient outcomes. In this thesis, we have beeninterested in three applications. The first one is related to the wettability measurement, especially forthe human skin. So we propose, a held-hand device that is based on the contact angle measurementto determine skin wettability. Besides, the device allows the visualization of the liquid dropletspreading in both dynamic and static modes. Moreover, it can measure the top and the left views ofthe droplet and provides the 3D droplet and the skin explored area profiles. The second applicationpermits the skin radiance measurement. For this purpose, we propose a miniaturized device havingan original method for the BRDF measurement associated with 3D profile measurement of the areastudied. As regards the third application, it is a non-invasive method for breath measurement that usesa stereovision system and a pseudo-periodic pattern. This system allows a high-resolution threedimensionaldisplacement measurement for the recording of the thoracoabdominal wall respiratorymovement. The devices developed during this research gives us a high accuracy, a good resolutionand repeatability of measurements

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Gmeinwieser, Korbinian, and Nikolas Schock. "Augmented Reality Contact Lenses: An Investigation of Technology Acceptance Drivers from a Potential User Perspective." Thesis, Jönköping University, Internationella Handelshögskolan, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-49347.

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Background: Augmented Reality (AR) could be the next revolutionary technology after the personal computer, the internet and the mobile era. While AR Smart Glasses are already on the market, AR Contact Lenses (ARCL) are still in the stage of research and development, but likely to replace the smartphone in the near future. Purpose: The purpose of this thesis is the identification of key factors influencing the acceptance of ARCL from a potential user perspective to gather early-stage pre-market knowledge and extend the Technology Acceptance Model (TAM) literature to this novel wearable technology. Method: An explanatory online survey was conducted to test the hypotheses in an extended TAM. Data from 250 respondents up to an age of 34 years, representing the potential target group was collected. Partial Least Squares Structural Equation Modeling (PLS-SEM) was used to assess the measurement model in terms of validity and reliability and the structural model in terms of hypotheses testing and strength of relationships between proposed variables. In addition, a multigroup analysis was examined to identify significant differences among groups. Conclusion: The results show that the attitude, which is strongly influenced by perceived usefulness, is the major key determinant affecting potential users’ behavioral intention to adopt ARCL in the future, followed by subjective norms. Furthermore, a strong influence of personal innovativeness on both antecedents of attitude, perceived usefulness and perceived ease of use was identified. Moreover, moderating effects of educational background, knowledge of ARCL and usage of contact lenses were discovered.

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3

Коркішко, Анастасія Олександрівна. "Система забезпечення надійності транзакцій з використанням технології блокчейн". Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/34815.

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Кваліфікаційна робота включає пояснювальну записку (59 с., 34 рис., 3 табл., список використаної літератури з 12 найменувань, 3 додатки). Метою бакалаврського дипломного проєкту є аналіз надійності технології blockchain та розроблення приватного blockchain для підвищення надійності грошових переказів та написання смарт контракту для виконання фінансових транзакцій всередині приватного blockchain. Для досягнення даної мети був проведений ретельний аналіз переваг та недоліків технології blockchain, дослідження різновидності смарт контрактів та способи їх написання, порівняння принципів роботи proof of work та proof of stake, порівняння їх діяльності. В результаті було розроблено приватний blockchain та написано смарт контракт для реалізації фінансових транзакцій. Протестовано роботу смарт контракту та продемонстровано результати його роботи в дипломному проєкті. Розроблений приватний блокчейн та смарт контракт можна успішно використовувати в фінансових структурах для грошових переказів між користувачами.
Qualification work includes an explanatory note (59 pages, 34 figures, 3 tables, list of references from 12 items, 3 appendices). The aim of the bachelor's thesis project is to analyze the reliability of blockchain technology and develop a private blockchain, to increase the reliability of money transfers and write a smart contract to perform financial transactions within a private blockchain. To achieve this goal, a thorough analysis of the advantages and disadvantages of blockchain technology, a study of the variety of smart contracts and ways to write them, a comparison of the principles of proof of work and proof of stake, a comparison of their activities. As a result, a private blockchain was developed and a smart contract was written to implement financial transactions. The work of the smart contract was tested and the results of its work in the diploma project were demonstrated. The developed private blockchain and smart contract can be successfully used in financial structures for money transfers between users

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4

Foo, Xueyuan. "Design and Implementation of A Smart Grid System Based on Blockchain Smart Contract Technology." Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-40851.

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Under de senaste åren har blockchain-tekniken fått mer och mer uppmärksamhet. Det har visat speciella fördelar i digital valuta, eftersom det distribueras och dess data inte kan ändras. Med fler länder som presenterar idén om kraftsysteminnovationen har ett stort antal distribuerade kraftkällor dykt upp. Nätanslutningen för dessa distribuerade kraftkällor leder till instabil nätdrift och ökar svårigheten att hantera kraftigt. Därför finns det ett akut behov av en lösning som kan realisera direkt transaktion av distribuerad kraftförsörjning. Denna artikel gör en fördjupad analys av blockchain-tekniken, inklusive hasalgoritm, konsensusmekanism, Merkle-träd, smart kontrakt etc. Och sedan studeras Ethereum och smarta nät. Den här artikeln realiserar automatisering och intelligens för mätning av eltransaktioner genom smart kontraktsteknik som tillhandahålls av Ethereum. En blockchain privat kedja skapas och sedan distribueras det smarta kontraktet i den privata kedjan. Med fördelarna med blockchaintekniken ovan kommer lagring av kraftdata och krafttransaktioner att vara mer trovärdig och mer transparent. Sammantaget designar och bygger detta papper ett smart grid-system baserat på blockchain-smarta teknik. Systemet kan inte bara användas för smarta nätsystem utan även för andra energisystem. Denna artikel ger en referens för tillämpning av blockchain-teknik.
In recent years, blockchain technology has received more and more attention. It has shown special advantages in digital currency, because it is distributed and its data cannot be altered. With more countries put forward the idea of the power system innovation, a large number of distributed power sources have emerged. The grid connection of these distributed power sources will lead to unstable grid operation and greatly increase the difficulty of management. Therefore, there is an urgent need for a solution that can realize direct transaction of distributed power supply. This article makes an in-depth analysis of the blockchain technology, including hash algorithm, consensus mechanism, Merkle tree, smart contract, etc. And then the Ethereum and smart grids are studied. This article realizes automation and intelligence of the electricity transaction measurement through the smart contract technology provided by Ethereum. A blockchain private chain is created and then the smart contract is deployed into the private chain. With the advantages of blockchain technology aforementioned, the storage of power data and the power transactions will be more credible and more transparent. All in all, this paper designs and builds a smart grid system based on the smart contract technology of blockchain. The system can be used not only for smart grid systems but also for other energy trading systems. This article provides a reference for the application of blockchain technology.

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5

Li, Andy. "Smarta kontrakt i svensk avtalsrätt : Huruvida Smarta kontrakt och Blockkedjor är lämpliga Avtalsinstrument." Thesis, Uppsala universitet, Juridiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-401562.

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The objective of this thesis paper is to investigate whether if smart contracts concluded on a blockchain are recognized as contracts under Swedish law. This is done by analyzing two fictional examples of concluded smart contracts. The study shows that smart contracts may indeed be recognized as contracts as they fulfill mechanisms for concluding contracts that are regulated in the Swedish Contracts Act, such as offer-acceptance. Smart contracts may also be concluded on mechanisms that are not directly regulated by the Contracts Act, these include tacit agreements and standard form of contracts. The objective also includes discussions regarding certain legal issues that are raised by the blockchain and smart contracts. For instance, what problems an immutable blockchain may pose for the possibility to recall an offer or acceptance stated in the Contracts Act. Another aspect that may also potentially prove troublesome is the smart contracts self-fulfillment. This is because they can facilitate the automatic fulfillment of contracts that are null and void due to the fact that they comprise illegal or immoral undertakings.

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6

Nordberg, William. "A SYSTEMATIC MAPPING STUDY ON DEVELOPMENT OF BLOCKCHAIN-BASED SMART CONTRACTS." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-54624.

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Context - Blockchain-based smart contracts have drawn the attention of scientific communities and businesses in recent years. The development of blockchain-based smart contracts is different from the development of conventional software due to the blockchain characteristics such as immutability, trustlessness, being append-only, and being decentralized. Therefore, standard software engineering processes need to be adjusted to address the unique characteristics of blockchain. Objective - This thesis aims to create a structured map of current research on the development of blockchain-based smart contracts, with a focus on identifying and classifying the development phases. Method - To accomplish our objective, we carried out a systematic mapping study on blockchain-based smart contract development. Our search yielded 1257 potentially related studies that were subjected to a selection process. Subsequently, in the final set appeared 41 primary studies. Result - Our main findings after analysis of the data are as follow: (i) researches mainly contribute to methods and providing tools, (ii) a large number of workshop papers indicate smart contracts' high acceptance rate, (iii) there is a lack of research on the finalization as a development phase, (iv) there is no common or standard language for specifying smart contracts that are valid regardless of the blockchain platform, (v) the most common language paradigm for smart contracts specification is imperative/declarative and for smart contracts implementation is declarative, (vi) the research community has put too much effort into the Ethereum blockchain, while it requires putting more attention to other blockchains, and (vii) there is a lack of studies tackling trustworthy oracle and scam challenges. conclusion - These results can benefit the research community to identify trends, constraints, and research gaps. In addition, they share potential directions for future research.

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7

Ozcan, Fatma Rana. "Category-Based Analysis of Smart Contracts." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563872670303612.

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8

Vattikutti, Avinash. "Potential of Smart Contract in Business to Business." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246063.

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The implementation of smart contract technology with their plausible applications in a business to business are explored. The thesis work shows how Blockchain technology works on the concept of decentralized system which is beneficial to eliminate the need for central authority. The thesis focuses on elimination of challenges pertaining to the selected departments in an organization. The thesis resolves challenges pertaining to lack of transparency, traceability and significant time-delays while in the process of decision making. The influence of blockchain technology and smart contract technology to eliminate these challenges are discussed. Logic of the smart contract and working of the blockchain pertaining to a specific industrial case study are demonstrated. Methodology to set up a smart contract interface in a business to business setting is investigated in this thesis. An observation study has been done in order to show how transparency, traceability and time delay in decision making is achieved by using smart contract interface. This thesis also shows how the blockchain and smart contract technology tries to implement coordination theory.

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Lepse, James LeVoy. "What to Buy: the Underexplored Dimension of the Smart-buyer Problem." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/50623.

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Using one question of Donald Kettl\'s smart-buyer problem as the basis of investigation, this study empirically examines the relationship between five selected services contract characteristics related to requirements and evaluation ratings of 120 federal information technology investments. The five contract characteristics selected for investigation were: Contract Type, Extent Competed, Performance-Based Acquisition, Integrated Process Team, and Program Manager Qualification. Analysis of these characteristics is relevant because current federal acquisition policy advocates particular contract characteristics as the preferred methods of procurement and others as widely accepted best practices. The five selected contract characteristics were analyzed for over 200 information technology services contracts using two separate statistical tests and four variants of information technology investment ratings as the dependent variable. Empirical evidence failed to reject the null hypothesis that there is no statistically significant correlation between selected service contract characteristics related to contract requirements and investment ratings. This failure of rejection through multiple tests led to the conclusion that service contract requirements are not better defined in cases when they should be based on selected contract characteristics. In order to better inform and understand the quantitative findings, interviews were conducted with over 20 senior acquisition and information technology executives representing 11 different federal departments and industry. None of the senior executives interviewed disputed the null finding and nearly 70 percent of subject matter experts interviewed were unsurprised that the selected service contract characteristics did not correlate with investment ratings.
The lack of correlation between selected contract characteristics related to requirements and investment ratings indicates that service contract requirements definition is a significant problem for federal agencies. That conclusion was confirmed by interviews with senior subject matter experts who consistently stated that accurately defining and managing information technology service contract requirements is a genuine challenge facing the federal government today.
Although empirical evidence failed to reject the null hypothesis, subsequent interviews revealed other factors that may have greater bearing on requirements and acquisition program outcomes than the five selected service contract characteristics. They present promising topics that merit further research.

Ph. D.

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Andreoli, Riccardo. "Stima del Gas negli Smart Contract Ethereum: una Rassegna." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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Una blockchain è una struttura dati formata da blocchi dove vengono memorizzate le transazioni, questi blocchi sono collegati tra di loro mediante un puntatore e il loro contenuto è reso sicuro sfruttando tecniche di crittografia; una delle blockchain più diffuse è quella di Ethereum. Ethereum non si occupa solo di inserire dentro i propri blocchi delle semplici transazioni, ovvero uno spostamento di Ether (la criptovaluta di Ethereum) da un account ad un altro, ma permette anche la creazione e pubblicazione di contratti intelligenti chiamati smart contract. Comunque, che si tratti di eseguire dalla più semplice delle transazioni al più complesso degli smart contract, Ethereum richiede una certa quantità di gas per poterlo fare. Il gas rappresenta il costo per poter eseguire qualunque operazione che si intende effettuare nella rete. Un problema legato al gas è quello di non sapere quanto ne viene effettivamente consumato prima che l'esecuzione, delle operazioni che si intendono fare nella blockchain di Ethereum, avvenga. Il fatto di non sapere a priori quanto gas viene utilizzato può portare ad errori come nel caso in cui la quantità massima di gas che un utente assegna ad uno smart contract risulti inferiore a quella necessaria affinché possa essere completamente eseguito. Questa tesi ha l'obbiettivo di spiegare il motivo per cui sarebbe utile poter riuscire a dare una stima della quantità di gas che verrà consumata e gli strumenti che sono in grado di farlo.

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Aaltonen, Antti Tapani. "Facilitating personal content management in smart phones." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 2007. http://irs.ub.rug.nl/ppn/300719086.

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Pettinari, Marina <1979&gt. "Context detection and abstraction in smart environments." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1123/.

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Context-aware computing is currently considered the most promising approach to overcome information overload and to speed up access to relevant information and services. Context-awareness may be derived from many sources, including user profile and preferences, network information, sensor analysis; usually context-awareness relies on the ability of computing devices to interact with the physical world, i.e. with the natural and artificial objects hosted within the "environment”. Ideally, context-aware applications should not be intrusive and should be able to react according to user’s context, with minimum user effort. Context is an application dependent multidimensional space and the location is an important part of it since the very beginning. Location can be used to guide applications, in providing information or functions that are most appropriate for a specific position. Hence location systems play a crucial role. There are several technologies and systems for computing location to a vary degree of accuracy and tailored for specific space model, i.e. indoors or outdoors, structured spaces or unstructured spaces. The research challenge faced by this thesis is related to pedestrian positioning in heterogeneous environments. Particularly, the focus will be on pedestrian identification, localization, orientation and activity recognition. This research was mainly carried out within the “mobile and ambient systems” workgroup of EPOCH, a 6FP NoE on the application of ICT to Cultural Heritage. Therefore applications in Cultural Heritage sites were the main target of the context-aware services discussed. Cultural Heritage sites are considered significant test-beds in Context-aware computing for many reasons. For example building a smart environment in museums or in protected sites is a challenging task, because localization and tracking are usually based on technologies that are difficult to hide or harmonize within the environment. Therefore it is expected that the experience made with this research may be useful also in domains other than Cultural Heritage. This work presents three different approaches to the pedestrian identification, positioning and tracking: Pedestrian navigation by means of a wearable inertial sensing platform assisted by the vision based tracking system for initial settings an real-time calibration; Pedestrian navigation by means of a wearable inertial sensing platform augmented with GPS measurements; Pedestrian identification and tracking, combining the vision based tracking system with WiFi localization. The proposed localization systems have been mainly used to enhance Cultural Heritage applications in providing information and services depending on the user’s actual context, in particular depending on the user’s location.

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13

Lee, Jack. "Smart Memory: An Inexact Content-Addressable Memory." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/4605.

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The function of a Content-Addressable Memory (CAM) is to efficiently search the information stored in the memory, by using hardware rather than software with a corresponding improvement in searching speed. This hardware allows a parallel search by matching the data stored in memory to a search key rather than sequentially searching address by address as is done in a Random Access Memory. Although existing CAMs are more efficient in finding relevant information than RAM, there are additional improvements that can be made to further improve its efficiency. For example, previous CAMs use a word parallel searching scheme that can only identify exact matches. To find the best (closest) match, previous CAMs had to use bit serial approaches. Although still more efficient than RAM searching, these CAMs were limited by the word size (bit width) of the memory. Responding to this inefficiency, the CAM described in this thesis improves best-fit searching by using analog design in combination with digital design. This design retains a mismatch line to collect the result of the comparison of each bit of a word which is decoded by a simple flash A/D. This means that after a single operation the best-fit plus all words with zero to three bits of mismatch, are determined. This word/bit parallel searching makes this CAM more efficient than existing CAMs. The best-fit function of this CAM is good for database retrieval, communications and error correction circuitry. By using the high speed searching and the inexact match feature, this CAM also provides efficient sorting and set operations. The accumulated searching time is shortened when compared to regular CAM and RAM. The inexact CAM in this thesis is designed using mixed analog/digital design in a 2~ CMOS technology.

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Kantur, Habil, and Charles Bamuleseyo. "How smart contracts can change the insurance industry : Benefits and challenges of using Blockchain technology." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Informatik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-39899.

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The world is becoming more and more digitized. Recently many industries have started to research the blockchain technology and particularly smart contracts. One industry that so far has not adopted new technology in the same pace as other industries, is the insurance industry so this interview study aims at finding opportunities and challenges for insurance companies that want to learn about smart contracts and its use cases.By doing a literature review and performing interviews with blockchain experts and insurance company employees, this study found that both IT companies working with smart contracts and the insurance companies have limited knowledge of the legal aspect of smart contracts. The lack of standards and regulations allows IT companies to freely create smart contracts without much quality control. The insurance companies must innovate themselves in order to not be disrupted. The blockchain technology will offer many new insurance types and if the insurance industry fails to adopt the blockchain technology they may face market disruption.There is much room for future research following this study. It would be beneficial to research how contract theory could be used in practice during the creation of legally binding smart contracts. Furthermore, research around fraud prevention in smart contracts would be interesting as would an in-depth exploration of the ecosystem of third party software and services around smart contracts.

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Bucciarelli, Stefano. "Un compilatore per un linguaggio per smart contract intrinsecamente tipato." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19573/.

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Borysenko, Yuliia. "Problems and prospects of practical application of smart - contract technolog." Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/53746.

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1. Insurance in the digital economy: problems and prospects. - [Electronic scientific professional publication]. - J .: MSU, 2018. - № 1. - Access mode: https://cutt.ly/pc9QUZt 2. Practical cases of application of blockchain - technologies in insurance in 2020. - [Electronic resource]. - Access mode: https://forinsurer.com/news/20/12/01/38816 3. Why is a blockchain in insurance a chance for an entrepreneur? - [Electronic edition]. - Access mode: https://cutt.ly/7c9QSAx 4. Blockchain (new) insurance. - [Electronic resource]. - Access mode: https://cutt.ly/Kc9QKpk 5. Internet insurance in Ukraine: problems and prospects. - [Electronic resource]. - Access mode: https://cutt.ly/Jc9hxZ6 6. Features of insurance development in the context of the Internet. - [Electronic resource]. - Access mode: https://cutt.ly/Tc9h9mO 7. Internet - marketing in the activities of insurance companies. - [Electronic resource]. - Access mode: https://cutt.ly/9c9j2ce
The necessity of using the technology of smart contracts in the conditions of digitalization of the world economy is investigated in the work. The aim of the study is to determine the essence of a smart contract, its relationship with the digital economy, blockchain technology and legal legislation. The definition of the basic economic concepts of digital economy is given, and also the basic advantages and lacks of use of smart - contracts in the conditions of modern economy and legal legislation are defined.

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Hallberg, Josef. "Context-sharing and mediated communication for smart environments." Doctoral thesis, Luleå : Department of Computer Science and Electrical Engineering, Division of Media Technology, Luleå University of Technology, 2008. http://epubl.luth.se/1402-1544/2008/66.

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18

Manzaroli, Daniele <1978&gt. "Architectures for Context Aware Services in Smart Environments." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2569/.

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This thesis deals with Context Aware Services, Smart Environments, Context Management and solutions for Devices and Service Interoperability. Multi-vendor devices offer an increasing number of services and end-user applications that base their value on the ability to exploit the information originating from the surrounding environment by means of an increasing number of embedded sensors, e.g. GPS, compass, RFID readers, cameras and so on. However, usually such devices are not able to exchange information because of the lack of a shared data storage and common information exchange methods. A large number of standards and domain specific building blocks are available and are heavily used in today's products. However, the use of these solutions based on ready-to-use modules is not without problems. The integration and cooperation of different kinds of modules can be daunting because of growing complexity and dependency. In this scenarios it might be interesting to have an infrastructure that makes the coexistence of multi-vendor devices easy, while enabling low cost development and smooth access to services. This sort of technologies glue should reduce both software and hardware integration costs by removing the trouble of interoperability. The result should also lead to faster and simplified design, development and, deployment of cross-domain applications. This thesis is mainly focused on SW architectures supporting context aware service providers especially on the following subjects: - user preferences service adaptation - context management - content management - information interoperability - multivendor device interoperability - communication and connectivity interoperability Experimental activities were carried out in several domains including Cultural Heritage, indoor and personal smart spaces – all of which are considered significant test-beds in Context Aware Computing. The work evolved within european and national projects: on the europen side, I carried out my research activity within EPOCH, the FP6 Network of Excellence on “Processing Open Cultural Heritage” and within SOFIA, a project of the ARTEMIS JU on embedded systems. I worked in cooperation with several international establishments, including the University of Kent, VTT (the Technical Reserarch Center of Finland) and Eurotech. On the national side I contributed to a one-to-one research contract between ARCES and Telecom Italia. The first part of the thesis is focused on problem statement and related work and addresses interoperability issues and related architecture components. The second part is focused on specific architectures and frameworks: - MobiComp: a context management framework that I used in cultural heritage applications - CAB: a context, preference and profile based application broker which I designed within EPOCH Network of Excellence - M3: "Semantic Web based" information sharing infrastructure for smart spaces designed by Nokia within the European project SOFIA - NoTa: a service and transport independent connectivity framework - OSGi: the well known Java based service support framework The final section is dedicated to the middleware, the tools and, the SW agents developed during my Doctorate time to support context-aware services in smart environments.

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Guo, Tjelvar, and Herzegh Daniel Han. "Availability of Smart Contracts that Rely on External Data." Thesis, Linköpings universitet, Programvara och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-169358.

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Smart contracts are digital agreements stored and executed on a blockchain. With smart contracts, multiple parties can enter into an agreement whose correct execution is guaranteed by the underlying blockchain. However, there is no inherent way for smart contracts to access data APIs external to the blockchain they reside on, which is needed in order to expand their usefulness. This thesis investigates two approaches of feeding data to a smart contract on the Ethereum blockchain, with regard to the performance metrics gas cost, block delay, and network latency. The investigation is set in the context of train travel where the time of arrival of a train at its destination is retrieved to the smart contract. Receiving and aggregating submissions from varying numbers of passengers is compared to retrieving this data from the dedicated open API provided by Trafikverket using the Chainlink framework. Through experiments, involving issuing transactions and monitoring them, it was found that in the case of passenger submissions with aggregation the gas costs had a linear relationship to the amount of passengers submitting data. Compared to lower amounts, the block delay for passenger submissions started seeing an increase at 100 to 300 submissions whereas it was more or less constant for aggregations. Furthermore, there was no noticeable trend for increase in network delay with increase of submissions. Conclusively, with regard to all performance metrics, it was found that in all cases involving more than five passengers it was cheaper to use Chainlink to fetch data from Trafikverket.

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Бичок, А. В. "Розробка Smart-контракта в месенджер на основі блокчейн". Thesis, Чернігів, 2020. http://ir.stu.cn.ua/123456789/23434.

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Анотація:

Бичок, А. В. Розробка Smart-контракта в месенджер на основі блокчейн : випускна кваліфікаційна робота : 123 "Комп’ютерна інженерія" / А. Ю. Акусок ; керівник роботи В. А. Бичко ; НУ "Чернігівська політехніка", кафедра інформаційних та комп’ютерних систем. – Чернігів, 2021. – 88 с.
Дипломний проект на тему «Smart-контракт в месенджер на основi блокчейн» складається із вступу, основної частини, що містить розділи, в тому числі и програмну реалізацію, висновку й списку використаної літератури. Загальний обсяг роботи – 80 сторінок. Робота містить 22 рисунки. Список використаних джерел включає 51 джерел. В першому розділі були описані види смартконтрактів та стандарти смартконтрактів Ethereum. Розглянули ERC токени та описали іх переваги і функції, були описані види блокчейнів, також були описані існуючі месенджери та вивлені їх плюси і мінуси. В другому розділі розглянуто проектування системи, описано компоненти, які були застосовані при розробці, такі як WebRTC, Node.js, Web3.js, Solidity та описана Хеш-функція. Метою даного роботи є створення смарт-контрактів та системи, яка дозволила би безпечно здійснювати операції перевірки виконання поставлених завдань та передачі коштів за них.
Thesis project on the topic “Smart-contract in messenger based on a blockchain” consist of an introduction, the main partm which contains sections, including software implementation, conclusion and a list of references. The total amount of work – 80 pages. The work contains 22 figures. The list of sources used includes 51 sources. The first section described the types of smart contracts and Ethereum smart contract standards. ERC tokens were considered and their advantages and fuctions were decribed, types of blockchains were described, ecisting messengers were also described and their pros and cons were outlined. The second section discusses the design of the system, describes the components that were used in the development, such as WebRTC, Node.js, Web3.js, Solidity and describes the hash function. The purpose of this work is to create smart contracts and a system that would allow safe operations to verify the implementation of tasks and transfer funds for them.

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21

Wåhlin, Johannes. "Real Estate Tokenizing : Blockchain Technology in Real Estate." Thesis, KTH, Fastigheter och byggande, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298315.

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Real estate assets are often considered as illiquid due to capital and transaction barriers. As a response, real estate tokenizing is a rising phenomenon. Real estate tokenizing combines the benefits from the private and the public real estate market, by creating a product with direct real estate commitment to low capital requirements and efficient transaction processes. The product is called real estate token, a digital share of an asset. Real estate tokens enable hypothetical fractionalization of properties with means of blockchain technology and smart contracts. This study investigate the pros and cons of real estate tokenizing as well as the financial performance of publicly traded US residential real estate tokens. The study states that fractionalization of properties increases access and customizability of real estate investments. Furthermore, the blockchain technology and the smart contracts enable automatization of transaction processes and asset management. Altogether, the benefits may result in a higher liquidity. However, the study also states several drawbacks with real estate tokenizing, such as lack of management and deeds, scalability problems and liquidity paradoxes. Furthermore, this study shows that US residential real estate tokens underperform both S&P 500 and housing index in terms of risk-adjusted return. Moreover, the real estate token market seems to correlate more with the S&P 500 than with the housing market. The study concludes that the cons with real estate tokenizing exceed the pros, although the phenomenon has great potential in a more mature market. However, real estate tokenizing will face implementation obstacles when converting the real estate industry to blockchain technology. As such, the success of real estate tokenizing is dependent on the global view of blockchain technology.
Fastigheter betraktas ofta som illikvida på grund av kapital- och transaktionsbarriärer. Som svar på den bristande likviditeten är blockchainteknologi inom fastigheter, även känt som ”real estate tokenizing”, ett växande fenomen. Real estate tokenizing ämnar till att kombinera fördelarna från den privata och den publika fastighetsmarknaden genom att skapa en produkt med direkt fastighetsexponering till låga kapitalkrav och effektiva transaktionsprocesser. Produkten kallas ”real estate token”, en digital andel av en tillgång. Real estate tokens möjliggör hypotetisk fraktionering av fastigheter med hjälp av blockchainteknologi och smarta kontrakt. Denna studie undersöker för- och nackdelar med real estate tokenizing såväl som finansiell prestation av publikt handlade real estate tokens inom det amerikanska bostadssegmentet. Studien konstaterar att fraktionering av fastigheter ökar tillgängligheten och anpassningsbarheten i fastighetsinvesteringar. Vidare möjliggör blockchainteknologi och smarta kontrakt automatisering av transaktionsprocesser och förvaltning. Sammantaget kan fördelarna med real estate tokenizing leda till högre likviditet. Studien konstaterar emellertid också flera nackdelar med real estate tokenizing, såsom brist på management och panträtt, storskalbarhetsproblem och likviditetsparadoxer. Vidare visar studien på att publikt handlade real estate tokens inom det amerikanska bostadssegmentet underpresterar både S&P 500 och bostadsindex i termer av riskjusterad avkastning. Dessutom verkar marknaden för publikt handlade real estate tokens inom det amerikanska bostadssegmentet korrelera mer med S&P 500 än med bostadsmarknaden. Studien konkluderar att nackdelarna med real estate tokenizing överstiger fördelarna i dagsläget, även om fenomenet har stor potential på en mer mogen marknad. Real estate tokenizing riskerar dock att möta implementeringshinder när fastighetsbranschen ska konverteras till blockchainteknologi. Således är framgången för real estate tokenizing beroende av den globala synen på blockchainteknologi.

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22

Harz, Dominik. "Trust and verifiable computation for smart contracts in permissionless blockchains." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209430.

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Анотація:

Blockchains address trust through cryptography and consensus. Bitcoin is the first digital currency without trusted agents. Ethereum extends this technology by enabling agents on a blockchain, via smart contracts. However, a systemic trust model for smart contracts in blockchains is missing. This thesis describes the ecosystem of smart contracts as an open multi-agent system. A trust model introduces social control through deposits and review agents. Trust-related attributes are quantified in 2,561 smart contracts from GitHub. Smart contracts employ a mean of three variables and functions and one in ten has a security-related issue. Moreover, blockchains restrict computation tasks. Resolving these restrictions while maintaining trust requires verifiable computation. An algorithm for verifiable computation is developed and implemented in Solidity. It uses an arbiter enforcing the algorithm, computation services providing and verifying solutions, and a judge assessing solutions. Experiments are performed with 1000 iterations for one to six verifiers with a cheater prior probability of 30%, 50%, and 70%. The algorithm shows linear complexity for integer multiplication. The verification depends on cheater prior probability and amount of verifiers. In the experiments, six verifiers are sufficient to detect all cheaters for the three prior probabilities.
Blockchains adresserar tillit genom kryptografi och konsensus. Bitcoin är den första digitala valutan utan betrodda agenter. Ethereum utökar denna teknik genom att möjliggöra agenter i blockchain, via smart contracts. En systemisk förtroende modell för smart contracts i blockchains saknas emellertid. Denna avhandling beskriver ekosystemet för smarta kontrakt som ett öppet multi-agent system. En förtroendemodell introducerar social kontroll genom inlåning och granskningsagenter. Tillitrelaterade attribut kvantifieras i 2,561 smart contracts från GitHub. De använder ett medelvärde av tre variabler och funktioner med en av tio som har en säkerhetsre-laterad fråga. Dessutom blockchains begränsa beräkningsuppgifter. Att lösa dessa begränsningar samtidigt som du behåller förtroendet kräver kontrollerbar beräkning. En algoritm för verifierbar beräkning utvecklas och implementeras i Solidity. Den använder en arbiter som tillämpar algoritmen, computation services som tillhandahåller och verifierar lösningar och en judge som bedömer lösningar. Experiment utförs med 1000 iterationer för en till sex verifierare med en snyggare sannolikhet för 30%, 50% och 70%. Algoritmen visar linjär komplexitet för heltalsmultiplicering. Verifieringen beror på fuskans tidigare sannolikhet och antal verifierare. I experimenten är sex verifierare tillräckliga för att detektera alla cheaters för de tre tidigare sannolikheterna.

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23

Ghelli, Melania. "Analisi Statica di Smart Contract in Ethereum: Stimare i Consumi di Gas." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19612/.

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Il gas è l'unità di misura dello sforzo computazionale richiesto per eseguire un programma in Ethereum. Questo carburante ha un costo, espresso in ether, l'unità di conto di Ethereum. È necessario acquistare il gas prima che il programma venga eseguito. Per questa ragione talvolta può accadere che durante l'esecuzione si esaurisca e che quindi il programma si blocchi. Siccome una situazione di questo genere può comportare una perdita di denaro, è preferibile agire sul codice prima della sua esecuzione, in modo da evitare spiacevoli inconvenienti. In questo contesto entra in gioco l'analisi statica: permettendo di verificare le proprierà dei programmi prima che vengano eseguiti, può essere applicata ai programmi di Ethereum per stimarne i consumi di gas. Questo compito non è poi così semplice. Vedremo quali sono le tecniche di analisi utili a stimare i consumi di gas, e quali sono i limiti di questa analisi.

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Santos, João Pedro Nunes dos. "Identity management in healthcare using blockchain technology." Master's thesis, Universidade de Évora, 2018. http://hdl.handle.net/10174/24008.

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Анотація:

Bitcoin served as the catalyst for creating a solution to secure digital transactions without requiring a trusted third party to be involved. To solve this problem, the mechanisms now associated with a Blockchain were conceptualized and implemented to serve as the backbone for the Bitcoin network. More specifically, it was used as a security tool making Bitcoin a more transparent and reliable form of cash, a digital cryptographic currency. Even tough Bitcoin ended up not fulfilling its intended purpose as a currency, the Blockchain technology has enabled further avenues for innovation and creativity. Blockchain has since been used as the backbone for various cryptocurrencies networks. Some implementations of this technology allow the execution of code, also known as ”smart contracts”. Smart contracts are executed in an autonomous manner, with no human intervention. These can be used to solve a new set of problems due to their transparent behavior, lack of human intervention and distributed nature. Blockchain technology allows the creation of systems that introduce a number of benefits over traditional data handling used in today’s Healthcare Information Systems. Costs and risks associated with these systems can be reduced and information can become transparent and trustworthy to all participants. The Hyperledger Fabric Network with true private transactions and advanced security mechanisms was used to serve as the basis for the system proposed in this dissertation. Moreover, a client application was also created that interacts with smart contracts to manipulate the ledger. The work discussed in this dissertation shows that a Blockchain system based on Hyperledger Fabric is suitable for managing patients identity, in Healthcare. Even tough the feature set of this Blockchain is very focused in privacy and security, some additional measures regarding confidentiality of data had to be implemented. Regardless, a system was built successfully that met the requirements. The implementation of this system would provide transparency, immutability and additional security for patients and medical staff alike; Sumário: Gestão de Identidade nos Serviços de Saúde Utilizando Tecnologia Blockchain A criptomoeda Bitcoin foi essencial para criar uma solução para transacções digitais seguras, sem requerer a participação de um terceiro interveniente fidedigno para ambas as partes. Para resolver este problema, os mecanismos que hoje são associados com a tecnologia Blockchain foram concebidos e implementados para servir como base para a rede da Bitcoin. Mais especificamente, esta foi utilizada como um mecanismo de segurança, de forma a tornar a Bitcoin uma forma de dinheiro mais transparente e estável, uma moeda criptográfica. Mesmo que a Bitcoin não tenha conseguido cumprir o seu propósito original, a tecnologia Blockchain despoletou novas inovações e permitiu maior criatividade. A Blockchain tem sido, desde então, a base tecnológica de várias criptomoedas. Algumas implementações desta tecnologia permitem a execução de código de uma forma autónoma exactamente como foi programado, sem intervenção humana. Habitualmente chamados smart contracts, estes podem ser usados para resolver um novo conjunto de problemas devido ao seu comportamento transparente, ausência de intervenção humana e devido à sua natureza distribuida. A Blockchain é uma tecnologia que permite a criação de sistemas que introduzem um conjunto de beneficios em relação aos sistemas tradicionais de armazenamento de dados utilizados nos serviços de saúde. Custos e riscos associados a estes sistemas podem ser reduzidos e a informação pode ser mais transparente e fidedigna para todos os participantes. A rede Hyperledger Fabric com transacções privadas e mecanismos avançados de segurança foi usada como base para a criação do sistema proposto nesta dissertação. Adicionalmente, uma aplicação foi criada que usa smart contracts para manipular o ledger da Blockchain. O trabalho apresentado nesta dissertação mostra que um sistema baseado em Blockchain, neste caso em Hyperledger Fabric, é adequado a gerir a identidade de utentes, em organizações prestadoras de cuidados de saúde. Apesar das funcionalidades apresentadas por esta plataforma serem focadas em privacidade e segurança, algumas medidas adicionais em torno da confidencialidade dos dados tiveram de ser implementadas. Independentemente disso, o sistema foi construido com sucesso e conseguiu cumprir os requerimentos que foram definidos. A implementação deste sistema em serviços de saúde traria tranparência, imutabilidade e segurança adicional para utentes e profissionais de saúde.

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Celen, Mustafa, and Maximiliano Rojas. "Value Creation From User Generated Content for Smart Tourism Destinations." Thesis, Högskolan Dalarna, Mikrodataanalys, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-34430.

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Анотація:

This paper aims to show how User Generated Content can create value for Smart Tourism Destinations. Applying the analysis on 5 different cases in the region of Stockholm to derive patterns and opportunities of value creation generated by UGC in tourism. Findings of this paper is also discussed in terms of improving decision making, possibilities of new business models and importance of technological improvements on STD’s. Finally, thoughts on models are presented for researchers and practitioners that might be interested in exploitation of UGC in the context of information-intensive industries and mainly in Tourism.

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Hellbe, Anton, and Gustaf Bohlin. "Evaluating IoT cloud platforms in the context of smart buildings." Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20027.

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Анотація:

Smarta byggnader är ett vanligt användningsområde för både Internet of Things (IoT)enheter och molntjänster. På senare tid har molntjänstleverantörer som Amazon, Googleoch Microsoft börjat erbjuda IoT-molnplattformar. Dessa består av en klass av tjänstersom utgör en bas för molnapplikationer som används av IoT-enheter. Idag finns det mångaolika leverantörer som tillhandahåller denna tjänsten och att välja en för en IoT-lösning ärsvårt. I denna rapport beskrivs utvecklingen av ett system som är vanligt förekommandei en smart byggnad. I denna rapport utvärderas IoT-molnplattformar för användninginom området smarta byggnader som en del av ett uppdrag från Sigma Lundinova. Förutvärderingen implementeras ett vanligt scenario i en smart byggnad som en prototyp medhjälp av två olika IoT-molnplattformar. Syftet med detta är att utvärdera och jämföra hurväl IoT-molnplattformarna stödjer utveckling av systemet beskrivet av scenariot. Genomatt implementera en prototyp insamlas underlag i form av kunskap och erfarenhet somanvänds i utvärderingen. Utvärderingen kan användas som ett hjälpmedel för att göradet lättare att välja en IoT-molnplattform när man utvecklar IoT-lösningar för smartabyggnader.
Smart buildings is a common application for both Internet of Things (IoT) devices andcloud services. Recently cloud service providers such as Amazon, Google and Microsofthave started to offer IoT cloud platforms which consist of a class of services that providea base for cloud applications utilized by IoT devices. However, there are many differentproviders of IoT cloud platforms and selecting one for an IoT solution for a smart buildingis difficult. In this thesis two IoT cloud platforms are evaluated in the context of smartbuildings as part of an assignment given by Sigma Lundinova. To evaluate the IoT cloudplatforms a common smart building scenario is realized by implementing a prototype usingtwo different IoT cloud platforms. The development process makes it possible to evaluatehow well the platforms support the development of the system that the scenario describes.The evaluation is based on information and experience from the process of developing thesystem using the IoT cloud platforms. The evaluation can be used as a guidance whenselecting IoT cloud platform for an IoT solution intended for a smart building.

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Nicanfar, Hasen. "Security and privacy in smart grid context : problems and solutions." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/55190.

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Анотація:

In order to improve the power grid and provision the Smart Grid concept, one well-defined approach would be to utilize new information and communication technology. Live power consumption data in addition to the time base power consumption rate are essential requirements in this context. These communications are supposed to be bi-directional between consumers, providers and smart grid administrations (market, operators, etc.). However, one of the most essential requirements that should be preserved is to address communication security and privacy. There are many opportunities for adversaries to attack the smart grid system, even remotely anywhere in the world, that could result in costly issues and damages in the system, even jeopardize user privacy. In the first part of this thesis, we concentrate on improving the efficiency of security mechanism and present our tailored authentication and key management mechanisms. We propose two solutions, one for communications between home appliances and a home gateway (smart meter), while the second solution aims at communications between the home smart meter and an appropriate server located in the smart grid utility network.We then propose enhancements on key management by developing two key construction mechanisms based on the Password Authentication Key Exchange (PAKE) protocol. The first is a cluster-based group key mechanism between smart grid entities, e.g. consumers in a neighbourhood area network. The second enhancement is a multi-layer key mechanism motivated by controlling the home smart appliances using different smart grid controllers located in different layers of the controlling hierarchy network. The second part of the thesis concentrates on Privacy. In this part, we present a privacy mechanism based on enhanced network coding for communications between smart meters and utility servers via a mesh topology. Finally, we propose a privacy-aware security solution for mobile devices. For example, to support electric vehicles in buying and selling the power from and to the grid, or in case of the smart phones in the heterogeneous network (4G and/or 5G), to support handover between the access points.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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28

Oliveira, Raul Alexandre Vaz. "Performance evaluation of smart contracts." Master's thesis, Universidade de Évora, 2022. http://hdl.handle.net/10174/31351.

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Анотація:

Blockchain is a distributed ledger with records of transactions made between accounts stored in it through blocks. This type of technology is becoming a part of our daily lives, due to its secure, immutable, verifiable and transparent nature. One relevant aspect of blockchain is that of smart contracts, these are very important and useful because they can automatically carry out certain actions based on what was written in its code. Transactions which should be carried out under specific conditions can be done more effectively by using a smart contract, which explicitly incorporates those conditions in its code. Since smart contracts are so critical, it is very important to make the correct decision when choosing a high-level language to use to code these agreements. Different languages that essentially do the same thing, can compile to a completely different set of instructions. The objective of this dissertation is to compare the performance of different smart contract high-level languages, set to carry out the same goal. We will compare languages from the Tezos and Ethereum blockchains. Different languages will produce different low-level code, some of which will be more efficient, as they will require less resources such as gas; Sumário: Avaliação do Desempenho de Smart Contracts Blockchain é um registo distribuído com documentações das transações feitas entre contas guardadas nele através de blocos. É bastante provável que este tipo de tecnologia faça parte do nosso dia-a-dia, devido à sua segura, imutável e transparente natureza. Um aspecto importante da blockchain são contractos inteligentes, estes são muito importantes e úteis por serem capazes de executar automaticamente certas ações baseadas no que foi escrito no seu código. Algumas transações com condições particulares podem ser feitas mais rapidamente se um contrato inteligente é utilizado e essas condições são escritas na sua lógica. Devido aos contratos inteligentes serem tão valiosos, é muito importante fazer a decisão correta na escolha de uma linguagem de alto nível para utilizar para programar estes acordos. Diferentes linguagens que essencialmente fazem o mesmo, podem compilar para um conjunto de instruções completamente diferente. O objectivo desta dissertação é comparar o desempenho de diferentes linguagens de alto nível de contratos inteligentes escritos para fazerem a mesma coisa. Vão haver comparações entre as linguagens das blockchains Tezos e Ethereum. Linguagens diferentes irão produzir diferentes códigos de baixo nível, considerando algumas destas linguagens mais eficientes, devido a requererem menos recursos como gas.

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Holmstedt, Sarah, and Malin Örnberg. "Smarta kontrakt - vägen mot en helt digitaliserad bank : En studie om blockchain-tekniken inom core banking." Thesis, Uppsala universitet, Avdelningen för datalogi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-358720.

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Анотація:

In the banking industry today there are processes in need of digitalisation to meet the digital needs of the customers. An area which is a candidate for digitalization is core banking which stands for Centralized Online Realtime Exchange and includes processes such as bank loans. By implementing the blockchain technology and smart contracts to core banking processes they can become digital and meet needs such as efficiency and transparency. The purposes of this master thesis are to examine the attitude Swedish banks have towards the blockchain technology, find out what core banking processes that could benefit from an implementation of a smart contract, and create an implementation model of a specific core banking process as a smart contract. By examining these topics a holistic perspective of how the blockchain technology can create value for the banks and customers can be reached to create a proof of concept model of a core banking process with the blockchain technology and smart contracts. The purposes are fulfilled by a literature study, interviews with representatives from Swedish banks, legal experts and requirements specialists and a model consisting of flowcharts, requirements,specifications, stakeholders and models in the blockchain platform Corda. Generally the banks have a positive attitude towards the blockchain technology but there are regulations that hinder the development process. Promissory notes was the process chosen to be implemented as a smart contract since itscharacteristics are fulfilled by the blockchain technology and according to thebanks this process would create the most value. According to a evaluation by the requirement experts at the employer Applicon the implementation model is suitable as a proof of concept and a good base for future prototyping.

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Törngren, Lisa. "BLOCK FÖR BLOCK : En jämförande studie mellan forskare och praktiker om blockkedjeteknik i revision." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-48368.

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Анотація:

Vilka möjligheter och utmaningar kan blockkedjetekniken erbjuda i revisionsprocessen? Studien ska undersöka samt skapa förståelse för de möjligheter och utmaningar som blockkedjetekniken medför inom revisionsprocessen och därmed bidra med ökad empirisk kunskap till det forskningsgap som identifierats inom den vetenskapliga litteraturen. Kvalitativ dokumentstudie som jämför vetenskapliga artiklar och dokument. De möjligheter som kan identifieras med blockkedjetekniken är trippelbokföring, smarta kontrakt, minskad tid, minskad kostnad, minskad risk, kodade kreditvärdighetsmodeller, minskat antal rättstvister, förenklar revisionsprocessen, blockkedjetekniken är omanipulerbar, ökad tillförlitlighet till revisorn, säkerhetskopiering, revisorn får en ny roll. De utmaningar som kan identifieras är ökad öppenhet, mindre transparens, kontrollera äkthet på överföringar, om blockkedjan kan manipuleras, farligt att lita till 100% på teknik, säkerhetskopiering, överskattad säkerhet, beskattning i realtid, skalbarhet, kostnader ökar i början, ekonomiutbildningar behöver anpassas, revisorns nya roll, revisorns nya arbetsuppgifter, nya kompetenser krävs, etik behövs, lagar och regler behöver anpassas, lagar behöver tillföras snabbare. Det är tydligt att många av möjligheterna också innebär utmaningar, det är sällan en möjlighet nämns utan att utmaningar med densamma tas upp. Det som också syns tydligt är att utmaningarna med blockkedjetekniken i dagsläget är fler än möjligheterna, vilket var ett oväntat resultat.
What opportunities and challenges can blockchain technology offer in the auditprocess? The study will investigate and create an understanding of the opportunities and challenges that blockchain technology entails in the audit process, thereby contributing with increased empirical knowledge to the research gap identified in the scientific literature. Qualitative documentstudy comparing scientific articles and documents. The opportunities that can be identified with blockchaintechnology are trippleaccounting, smart contracts, reduced time, reduced cost, reduced risk, coded creditworthiness models, reduced number of litigations, simplifies the auditprocess, blockchaintechnology is unmanipulable, increased reliability to the auditor, back-up, auditor’s new role. The challenges that can be identified are increased openness, less transparency, checking the authenticity of transfers, if the blockchain can be manipulated, dangerous to trust 100% on technology, backup, overestimated security, real-time taxation, scalability, costs increase in the beginning, financial education needs to be adapted , the auditor's new role, the auditor's new duties, new skills are required, ethics are needed, laws and regulations need to be adapted, laws need to be applied more quickly. It is clear that many of the opportunities also pose challenges; there is rarely an opportunity mentioned without challenges being addressed. What is also clearly seen is that the challenges with blockchain technology in the current situation are many more than the possibilities, which was an unexpected result.

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31

Starlander, Isak. "Counterparty Credit Risk on the Blockchain." Thesis, KTH, Matematisk statistik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215493.

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Анотація:

Counterparty credit risk is present in trades offinancial obligations. This master thesis investigates the up and comingtechnology blockchain and how it could be used to mitigate counterparty creditrisk. The study intends to cover essentials of the mathematical model expectedloss, along with an introduction to the blockchain technology. After modellinga simple smart contract and using historical financial data, it was evidentthat there is a possible opportunity to reduce counterparty credit risk withthe use of blockchain. From the market study of this thesis, it is obvious thatthe current financial market needs more education about blockchain technology.
Motpartsrisk är närvarande i finansiella obligationer. Den här uppsatsen un- dersöker den lovande teknologin blockkedjan och hur den kan användas för att reducera motpartsrisk. Studien har för avsikt att täcka det essentiel- la i den matematiska modellen för förväntad förlust, samt en introduktion om blockkedjeteknologi. Efter att ha modellerat ett enkelt smart kontrakt, där historiska finansiella data använts, var det tydligt att det kan finnas en möjlighet att reducera motpartsrisk med hjälp av blockkedjan. Från mark- nadsundersökningen gjord i studien var det uppenbart att den nuvarande finansiella marknaden är i stort behov av mer utbildning om blockkedjan.

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32

Shieh, Cheng-En, and 謝承恩. "Thin-Film Supercapacitor for Smart Contact Lens Applications: Design, Fabrication and Measurement." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/faps94.

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Анотація:

碩士
國立交通大學
電機工程學系
107
This paper reports a thin-film supercapacitor as an energy storage component for smart contact lens applications. Using flexible and biocompatible Parylene-C as the substrate and packaging material, graphene as the nano porous electrode material and solid-state polymer electrolyte (PVA-H3PO4) as electrolyte of the supercapacitor. The proposed thin-film supercapacitor is 37 μm thick and packaged in soft contact lens. Furthermore, the fabrication is compatible with the smart contact lens system which we have developed so there is almost no increase in cost. Then based on experiments, the proposed thin-film supercapacitor is packaged in a contact lens and can work in saline solution. Obtained the specific capacitance of 22.97 F/cm3 to 12.80 F/cm3. Finally, we integrate the thin-film supercapacitor, antenna, chip and load into contact lens. Complete a soft and high water-containing smart contact lens system with energy storage component. The results of this paper show the potential for future vision correction or eye disease related applications and proposed a new solution of energy source for future smart contact lens systems. In addition, the RFID based smart contact lens can be changed from passive system to semi-passive system, which can reduce the intensity and duration of exposing eye tissues to electromagnetic wave when using. Solved the problems in safety or clinical experiments that may encounter in future.

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33

Hsu, Shun-Hsi, and 徐舜熙. "Design, Fabrication, and Verification of Wireless Smart Contact Len System for Eye Healthcare Applications." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/sx5973.

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Анотація:

博士
國立交通大學
電機工程學系
106
Due to the invention and rapid development of multimedia devices such as smart mobile phone and tablet, people’s habits of using eyes have dramatically changed. Therefore, long-term monitoring of eye healthcare information attracts many research focuses in the past few years. Two major eye diseases, glaucoma and dry eye syndrome (DES), were used as illustrations for smart contact lens (SCL) developments in this research. This research proposed a wirelessly powered smart contact lens sensor system for long-term monitoring of eye healthcare conditions. The SCL sensor system consists of SCL readout system and a smart contact lens. SCL readout system uses commercial radio frequency identification (RFID) reader to transmit energy to smart contact lens and communicates with it through ultra-high frequency (UHF) EPCGlobal C1G2 protocol. The smart contact lens consists of capacitive or resistive sensors, receiving antenna and sensor chip. The on-lens biosensors are fabricated with Microelectromechanical Systems (MEMS) technology to implement sensor devices for impedance variations following eye conditions. The receiving antenna is used for energy transmission and data communication. The sensor chip is a RFID based sensor chip with embedded impedance-to-digital converter (IDC) for sensor data conversion. The eye healthcare information such as intraocular pressure (IOP) and tear evaporation rate was detected by capacitance change of on-lens capacitive or resistive sensors. The digital value after conversion by IDC will be transmitted back to external RFID reader through load modulation. The chip, receiving antenna and biosensor were integrated on a soft contact lens with commercially available biocompatible HEMA hydrogel by using a general cast molding method. With standard 200-μm thickness and commercial manufacturing process, discomfort of proposed SCL is reduced and compliance is increased. The proposed smart contact lens system enabled the detection of capacitive variation caused by pressure changes within the range of 2.25 to 30 mmHg and hydration level variation from a distance of 1 cm using 26.5 dBm incident power from commercial Gen2 RFID-compatible equipment. To sum up, the proposed SCL system can achieve wireless recording and long-term monitoring. The application of this system can be future extend by design and integration of different on-lens sensors for different biomarkers in the future.

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34

PAN, CHUN-PING, and 潘俊平. "A New Method for A Non-contact Respiration Rate Measurement System on The Smart Clothes." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2u5nj3.

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Анотація:

碩士
明新科技大學
電機工程系碩士在職專班
106
Breathing is an essential function of the human health, as the human body gets old, the function of the respiratory system will gradually decline and affects the respiratory efficiency especially older adults. Taiwan has more than 14% of the elderly population in May 2018, which increases the demand for related rehabilitation and life care. In this study, we develop a cotton based smart clothing with a new method of measuring respiratory rate for the elderly population. The cotton-based smart clothing is a home monitoring system which can provide alternative services for medical services. Compared with the traditional contact measurement that the sensor needs to be closely attached to the human body. Results in poor user comfort which is not subject to non-contact measurement, and can only be measured under certain circumstances. In this study, an optical sensor was used to design a non-contact measurement method. The infrared light was used to illuminate the surface of the chest and abdomen of the human body. The reflectance changes according to the breathing action of the human body. This method can have proper detection of respiratory action characteristics. By processing the hardware-based algorithm the respiratory rate can be calculated.

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35

Fan, Jiamin. "SmartSharing: a content delivery network with local sharing of over-the-top devices." Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/10125.

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Анотація:

Content delivery networks (CDNs) depend on distributed cache servers to reduce the content delivery distance and latency to end users. Nevertheless, a CDN's cache footprint is greatly limited by the high cost in deploying and maintaining large- scale cache servers. To break the limit, CDN providers adopt a new content caching strategy that allows end users to share their storage/bandwidth resources with each other. Two core questions need to answer in this CDN strategy: (1) how to incentivize end users to contribute their resources? and (2) how to facilitate transparent, secure content exchange among end users? We propose a new CDN solution, called SmartSharing, where users contribute their Over-the-top (OTT) devices as mini cache servers. With SmartSharing, an OTT device can share the content the OTT owner is downloading and in addition can cache content for neighboring OTT devices in the same area. To incentivize end users to contribute their resources, SmartSharing uses game theory and the Expectation- Maximization (EM) algorithm to determine content delivery schedule and the pricing scheme. To facilitate content trading among end users, SmartSharing uses smart contracts in Ethereum to create a transparent and safe transaction platform. We evaluate SmartSharing with real-world trace driven simulation as well as smart con- tract prototype in Ethereum using content meta-data and the derived pricing scheme. By disclosing the internal dynamics in content delivery schedule and pricing scheme and analyzing the overhead in content trading, we show that SmartSharing is an effective new CDN solution that benefi ts content providers, CDN, and end users.
Graduate

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36

Hsu, Tsan-Hsiang, and 徐粲翔. "Gcoin Smart Contract Architecture." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3m2b4q.

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37

KE, BAI-YUEH, and 柯百嶽. "Pallet.io : Cross-Chain Smart Contract." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/92fxzr.

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Анотація:

碩士
國立臺灣大學
資訊工程研究所
106
With the advent of Bitcoin in 2008, blockchain technology has been paid much attention to society every year and has inspired the development of many other blockchain technology. The idea smart contract, which was proposed in 1994, was successfully merged into Ethereum. It brings the development of blockchain technology into the next era. Smart contract is one of the most important features in blockchain technology nowadays, which allows users to trade money, property of anything valuable without a middleman. Compared to traditional contracts, it can save a lot of manpower, time, and resources, but can bring more stable and more secure results. After the advent of Ethereum, the development of blockchain-based smart contract flourished. There are many unique and valuable blockchain come out. However, every blockhain is parallel. It make the demand of cross-chain rising. This thesis proposes a cross-chain smart contract architecture that could connect most cryptocurrency and try to reach balance between difficulty, low-cost and trusty.

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38

Liu, Lee, and 劉皪. "State-based modifiable smart contract." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/ykt72w.

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Анотація:

碩士
國立政治大學
資訊管理學系
107
A smart contract deployed on the blockchain is meant to be immutable; however, in practice, the consensus and operations among parties may change as time goes by, e.g., to fix security frauds, leading to the need of flexibility on contract modification. We propose a state-based smart contract framework that facilitates contract modification, where a deployed smart contract can be altered partially with update operations or control logic while keeping previous transactions (blocks) consistent. Specifically, we divide an ordinary contract into four functional contracts that are linked by the framework to work together. The control contract manages the control logic with a finite state machine where transactions are guarded with version control to distinguish different versions of the contract; the storage contract that accesses global variables synchronizes the view of state variables; the main contract implements the main part of application logic, and the update contract implements codes that are designed in a state-based fashion to allow to be swapped with update operations. We have implemented a proof-of-concept insurance smart contract to demonstrate how to develop, deploy, execute and alter a modifiable smart contract under the proposed framework.

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39

SUN, WEI-TING, and 孫尉庭. "Smart Contract Application in Funeral Industry." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8694p3.

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Анотація:

碩士
東海大學
高階經營管理碩士在職專班
106
This study aims to explore the characteristics of smart contracts in the blockchain: users can't deny that all changes can be tracked and recorded, it is difficult to tamper with credibility, confidentiality, to achieve the convenience of planning for the Pre Need funeral contract. Because of the rapid transformation of modern society, people have become gradually enlightened for the concept of endowment and end of life, and it is a task that everyone has to face the arrangement funeral. However, in the face of the end of life, people are still powerless for their own arrangements funeral, and in today’s society, the majority of people are degraded. People are still unable to arrange their own affairs behind the scenes, so the Pre Need funeral contract has become a way for people to confess things behind. However, the domestic contractual contractors only introduced stereotyped Pre-Need contracts, and most of the pre-Need contracts cannot meet individual needs. In the end, they returned to the origin to allow the burial industry to ask for permission so that future generations would be overwhelmed. The blockchain is a technology has started to develop for several years. It has become more mature in the development of smart contracts. Therefore, the purpose of this research is to explore the possibility of applying the content of a lifetime contract through the application of smart contracts in order to reach the individual’s wishes. The autonomy and convenience of the contract. Blockchain technology is open and transparent, and it cannot be faked. A program executed on a blockchain platform through smart contracts can ensure that the program will not be tampered with, and that all execution records can be completely preserved so that the lifetime contract can be achieved through this technology to facilitate the process of transparency and popularity. Help consumers to plan Pre-need faster, easier, safer, more professional and more transparent.

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40

WU, PENG-TA, and 鄔朋達. "Smart Contract of Organic Agriculture Subsidy." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/e7ucp8.

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Анотація:

碩士
東吳大學
資訊管理學系
107
Recently, the blockchain technology has been valued. With the support of resources across many industries, an increased number of innovations are made available, the emerging commercial modes in the financial technology in particular. The government, by employing the smart contracts, can change the way they deliver services and business processes to reduce the administrative cost. The government, in order to protect the interests of farmers, implements plural subsidy policies. The subsidy amount exceeds over half of the annual agricultural budget and the subsidy given to organic agriculture hikes year by year. Without being certified by organic agriculture certification companies, it is not allowed to make any organic claim. When farmers consider converting to organic, the costs may hinder their willingness, so the government grants subsidies to farmers in need of organic certification. The study employed the ethereum smart contract based on the blockchain technology to develop a prototype of the organic farming subsidy payment system. Compare the system with the current subsidy process, it shows that the system has the following advantages: 1. All applications must be submitted through the online application system, and farmers can apply for subsidies online at any time. 2. Integrate farmers' information flow into government's. E-procedures can reduce the working hours of review. 3. Using smart contracts to store data on the blockchain. With subsidies granted by cryptocurrency to ensure timely releases of funds.

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41

Xiong, Zhan-Xuan, and 熊展軒. "Ethereum Smart Contract Concurrent Execution Model." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/w6829t.

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Анотація:

碩士
國立臺灣大學
資訊工程學研究所
107
Since the advent of Bitcoin in 2008, the decentralized ledger system, based on blockchain technology, has flourished. Initially, in the world of Bitcoin, users are free to transfer their assets (Bitcoin) without a centralized organization. Bitcoin built the most reliable financial system in the virtual world. In the network, that the users are not trust in each other, asset transfer can still be performed based on such the system. In 2013, Vitalik Buterin proposed a new generation of decentralized ledger system, Ethereum. Ethereum added a complete programming language based on the core concept of blockchain to enable people to develop applications on it. Users can develop their own application and let it run in a decentralized environment, such a program is also known as a smart contract. Today''s Ethereum as a smart contract implementation platform is very mature, a variety of Decentralized applications are operating very well in Ethereum, but still face the bottleneck of all current decentralized ledger system, that is scalability. The scalability of the decentralized ledger system is mainly to describe the ability of the system to process transaction requests. It can be regarded as the performance or throughput of the system intuitively. The scalability is also one of the most important topics of blockchain technology today. The main goal of this thesis is to enhance the efficiency of Ethereum''s smart contracts through parallelization without changing current Ethereum architecture (The block and transaction format remain the same). By this way, we can enhance the scalability of the Ethereum system.

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42

Mendes, Diogo Alexandre Valente. "Smart-contract Blockchain with Secure Hardware." Master's thesis, 2020. http://hdl.handle.net/10362/116772.

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Анотація:

In recent years, blockchains have grown in popularity and the main reason for this growth is the set of properties that they provide, such as user privacy and a public record of transactions. This popularity is verifiable by the number of cryptocurrencies currently available and by the current market value of Bitcoin currency. Since its introduction, blockchain has evolved and another concept closely linked with it is smart-contract, which allows for more complex operations over the blockchain than simple transactions. Nevertheless, blockchain technologies have significant problems that prevent it to be adopted as a mainstream solution, or at least as an alternative to centralized solutions such as banking systems. The main one is its inefficiency, which is due to the need of a consensus algorithm that provides total order of transactions. Traditional systems easily solve this by having a single central entity that orders transactions, which can’t be done in decentralized systems. Thus, blockchain’s efficiency and scalability suffer from the need of time-costly consensus algorithms, which means that they can’t currently compete with centralized systems that provide a much greater amount of transactional processing power. However, with the emergence of novel processor architectures, secure hardware and trusted computing technologies (e.g. Intel SGX and ARM TrustZone), it became possible to investigate new ways of improving the inefficiency issues of blockchain systems, by designing better and improved blockchains. With all this in mind, this dissertation aims to build an efficient blockchain system that leverages trusted technologies, namely the Intel SGX. Also, a previous thesis will serve as a starting point, since it already implements a secure wallet system, that allows authenticated transactions between users, through the Intel SGX. As such, this wallet system will be extended to provide traceability of its transactions through a blockchain. This blockchain will use Intel SGX to provide an efficient causal consistency mechanism for ordering transactions. After this, the following step will be to support the execution of smart-contracts, besides regular transactions.
Nos últimos anos, as blockchains tornaram-se bastante populares e o motivo é o conjunto de propriedades que fornecem, como a privacidade dos utilizadores e um registo público de transações. Essa popularidade é verificável pelo número de criptomoedas existentes e pelo atual valor de mercado da moeda Bitcoin. Desde a sua introdução, o conceito de blockchain evoluiu bastante e surgiu o conceito de smart-contract, que permite realizar operações mais complexas sobre uma blockchain, além de simples transações. Contudo, existem problemas que impedem blockchains de serem adotadas como so luções convencionais ou como uma alternativa a soluções centralizadas, como o caso de sistemas bancários. O seu principal problema é ineficiência, resultante da necessidade de um algoritmo de consensus que forneça ordem total das transações. Os sistemas tradi cionais resolvem esse problema facilmente, sendo que têm uma única entidade central que ordena transações, o que não pode ser feito em sistemas descentralizados. Assim, a eficiência e a escalabilidade das blockchains sofrem com a utilização de algoritmos de consensus dispendiosos, o que significa que não conseguem competir atualmente com sistemas centralizados que fornecem uma maior quantidade de poder de processamento transacional. No entanto, com o aparecimento de novas arquiteturas de processadores, hardware seguro e tecnologias de computação confiável (por exemplo, Intel SGX e ARM TrustZone), tornou-se possível investigar novas formas de melhorar os problemas de ineficiência dos sistemas de blockchain e a construção de sistemas melhores e mais eficientes. Assim sendo, esta dissertação visa construir uma blockchain eficiente com recurso ao Intel SGX. O ponto de partida será um sistema de wallet, que permite transações autenticadas entre usuários através do Intel SGX, desnvolvido numa dissertação anterior. Como tal, esse sistema será estendido para fornecer rastreabilidade das transações através de uma blockchain. Esta blockchain utilizará o Intel SGX para fornecer um mecanismo de consistência causal eficiente para a ordenação das transações. Depois disto, o passo seguinte será suportar a execução de smart-contract, além de simples transações.

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43

Fonseca, Vítor Alves. "Smart Content Relocation in Content-Centric Networks." Master's thesis, 2015. http://hdl.handle.net/10316/97172.

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Анотація:

Dissertação de Mestrado em Engenharia Informática apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
Information-Centric Networking (ICN) is a new networking concept devised to cope with the challenges faced by the current design of Internet communications, such as the rising number of users and the mobility of the devices. Although this concept already has some features that are relevant for current Internet usage, such as in-network caching capabilities and content replication, there are still some relevant improvements to be developed. One of the key aspects of ICN is the ability to deal with node mobility, since there are no persistent connections, making it stand out from the current Internet design. However, although ICN supports mobility, there are still no optimizations to better serve users on the move. By tracking the contents’ popularity at the users’ sources, it is possible to pre-cache related contents to the ones accessed by the users at their destination. This pre-caching allows to better serve those users when they arrive, providing reduced delays while obtaining the pre-cached contents. Content-Centric Networking (CCN) is one of the existent ICN architectures and here we propose an improvement to CCN mobility capabilities: smart relocation of contents, based on users’ movement. In this work, we design, implement and validate smart content relocation mechanisms able to integrate with the core system of CCNx to anonymously monitor data requests and relocate relevant data according to the users’ upcoming destination prior to their arrival. This will allow an improvement on the users’ service experience, namely regarding delay, when using CCN with content relocation.
Information-Centric Networking (ICN) é um novo conceito de redes criado com o objectivo de ultrapassar alguns dos obstáculos encontrados pela actual forma de comunicação da Internet, tais como o crescente número de utilizadores e a mobilidade dos dispositivos. A possibilidade de fazer caching por toda a rede e de replicar conteúdos são duas das características base deste novo conceito, que tem ainda muitos aspectos onde pode ser melhorado. No ICN não existem ligações permanentes entre dois nós, ao contrário do actual conceito da Internet, o que faz com que este consiga lidar bem com a mobilidade dos nós, um dos principais aspectos que se salienta comparando à actualidade. No entanto não foram ainda desenvolvidas nenhum tipo de optimizações para melhor responder aos utilizadores que estão em movimento. Através da monitorização dos conteúdos populares entre os utilizadores, é possível fazer um pre-caching quando estes se movem, para assim melhor a sua experiência quando chegam ao destino, nomeadamente apresentando atrasos menores. Content-Centric Networking (CCN) é uma das várias arquitecturas de ICN existentes à qual é proposta uma melhoria: relocalização inteligente de conteúdos com base no deslocamento dos utilizadores. Neste trabalho desenhamos, implementamos e validamos esta proposta e a sua integração com o sistema base do CCNx através da monitorização anónima dos conteúdos e da migração dos conteúdos relevantes para o destino dos utilizadores. Esta migração permitirá uma melhoria na experiência dos utilizadores, nomeadamente em termos de atraso quando usam CCN com a relocalização dos conteúdos.

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44

Lin, Hsiu-Ping, and 林修平. "Semi-Centralized Blockchain Smart Contract : Smart Contract of Centralized verification and Off-Chain Execution on Ethereum Blockchain." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/j2w3tk.

Повний текст джерела

Анотація:

碩士
國立臺灣大學
資訊工程學研究所
105
Smart contract deployed on Blockchain has the advantage of decentralization. However, with the increasing popularity and surging market cap of Blockchain tech- nology such as Ethereum, it has become much more expensive and difficult to deploy and execute a smart contract on Blockchain. We propose a semi-centralized smart contract architecture to move the smart contract execution and verification away from the Ethereum blockchain. We hope applications can improve efficiency and save execution cost of their smart contract by balancing the trade-off between centralization and decentralization while retain computation verifiability and tamper-proof data. We didn’t propose a new consensus algorithm or sharding scheme to increase transaction-per-second or compuation-per-second on Blockchain. What we proposed is a different approach to execute smart contract. User gets to decide between different property he desires such as centralization, decentralization, efficiency and computation-per-second and choose the best way to execute his smart contract.

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45

Fidalgo, Ana Ines Mesquita. "Smart Destination Apps." Master's thesis, 2018. http://hdl.handle.net/10316/83534.

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Анотація:

Dissertação de Mestrado em Engenharia Informática apresentada à Faculdade de Ciências e Tecnologia
The main goal of this internship was to develop a mobile application for Android and iOS that used concepts and technologies that still have not had its full potential explored in the context of touristic activities. These technologies included the use of Beacons and the concept of context-awareness. Throughout the internship period, the development of the mobile application focused on mapping points of interest from Porto, but one of the main concerns was to develop a system with a modular architecture, that would allow the app to be expanded and adapted to other cities and technologies. Through location services and the usage of Beacons, this mobile application intended to satisfy its user’s needs by widening the scope of touristic activities. This included giving the user information about Points of Interest or data from sensors at the time this information could become the most relevant, by knowing where they are, the available time they had to visit a certain location and what environment surrounded them. To develop this mobile application, not only it was necessary to perform a market study to understand what these types of apps are already offering to tourists, but also a study of concepts like beacons and context-awareness, to understand what advantages these types of mobile applications can take from using these technologies. After this analysis, it was deﬁned a set of requirements that were developed throughout the internship. For this, it was designed an architecture with the necessary quality attributes that could ﬁt these requirements. Another main concern of this internship was to guarantee that the ﬁnal prototype of the mobile application was intuitive, prioritizing the development of a simple but attractive interface design.
O objetivo principal deste estágio passou pelo desenvolvimento de uma aplicação móvel para Android e iOS que tivesse algumas características que ainda não foram exploradas em todo o seu potencial na área do turismo. Estas tecnologias incluíam o uso de Beacons e o conceito de context-awareness, "consciência de contexto". Ao longo do período de estágio, o desenvolvimento da aplicação móvel focou-se no mapeamento de pontos de interesse da cidade do Porto mas, um dos principais pontos de preocupação deste estágio era desenvolver um sistema com uma arquitetura modelar que permitisse que a aplicação fosse posteriormente expandida e adaptada a outras cidades e tecnologias. A partir de serviços de localização e do uso de Beacons, esta aplicação móvel pretende satisfazer as necessidades dos seus utilizadores através do aumento do âmbito das suas atividades turísticas. Este âmbito inclui fornecer ao utilizador informação acerca de Pontos de Interesse ou dados de vários tipos de sensores no momento em que esta se poderá tornar para ele o mais relevante. Para tal foi essencial saber onde estes utilizadores estão, quanto tempo têm disponível para visitar uma certa localização e o que compõe o ambiente que os rodeia. Para desenvolver esta aplicação móvel, não só foi necessário realizar um estudo de mercado para veriﬁcar que tipo de aplicações atualmente já são oferecidas aos turistas, mas também realizar um estudo sobre conceitos como beacons e context-awareness. Este estudo permitiu perceber que vantagens é que uma aplicação turística poderia retirar do uso destes conceitos e tecnologias. Depois desta análise foi deﬁnido um conjunto de requisitos que foram desenvolvidos ao longo do estágio. Para tal, foi deﬁnida uma arquitetura que suportasse tanto este conjunto de requisitos, bem como o conjunto de atributos de qualidade necessários à aplicação. Outro ponto considerado importante ao longo do estágio era garantir que o protótipo ﬁnal da aplicação móvel fosse suﬁcientemente intuitivo, prioritizando-se portanto o desenvolvimento de uma interface simples, mas atrativa.

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46

HSU, CHAN-YUAN, and 許展源. "Digital Rights Management Based on Smart Contract." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/n7q5x9.

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Анотація:

碩士
逢甲大學
資訊工程學系
105
Digital rights management (DRM) is widely used to control users’ access to digital content by limiting their rights to use, view, copy, and modify their purchased content. By preventing users from disseminating content without authorization, DRM protects the rights of digital content creators. DRM is mostly centrally managed. Sellers can unilaterally revoke the rights to access sold digital content, which hurts buyers’ interests. In this paper, smart contract technology and blockchain technology are leveraged to achieve decentralized digital content management. Digital content is sold only if buyers and sellers agree to decentrally managed smart contracts, meaning that established transactions could not be unilaterally withdrawn by the seller or buyer. Since digital content is managed in a distributed manner with our method, the smart contracts guarantee that the authors are paid for their effort when their work is used. Hence, our approach not only protects the rights of buyers and sellers but also helps to restrict piracy and enhances the feasibility of digital content being legally distributed under the DRM architecture. By replacing complicated piracy-curbing methods, our approach can encourage creation, raise revenue for the digital content industry, and create a win-win situation for creators and customers.

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47

Hsu, Hsuan, and 許軒. "OurContract: A Smart Contract Design on Bitcoin." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/jay89d.

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Анотація:

碩士
國立臺灣大學
資訊工程學研究所
106
Ethereum implements the first blockchain-based smart contract platform and successfully brings lots of decentralized applications. For Bitcoin and its derivatives, however, there are currently no mature implementations with smart contracts. Moreover, the Ethereum blockchain adopts the account model instead of the UTXO model as in Bitcoin to achieve account tracking, which is necessary for smart contracts but compromises some user privacy. In this thesis, we present OurContract, an alternative solution to smart contract platform built on the Bitcoin blockchain. We construct an additional account layer on top of the UTXO model to achieve account tracking while preserving the privacy property of the UTXO model. To make OurContract more practical, we design mechanisms to enable coin transfer among contract accounts and users, and we allow transaction fee to be determined according to the cost for miners to execute contracts. For users to develop OurContract applications, we provide a limited version of C, called C-, as the programming language, and an associated library, called libourcontract, for C- programmers to interact with the blockchain. Our work can be applied to not only Bitcoin, but any blockchains based on the UTXO model.

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48

Wei, Zhi-Hong, and 魏誌宏. "A Smart Contract-Based Mobile Ticketing System." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/2693c2.

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Анотація:

碩士
國立中山大學
資訊管理學系研究所
107
We develop a blockchain-based mobile ticketing system which utilizes smart contracts and multi-signature to enforce and authorize the executions of transactions. The transactions of buying and using mobile tickets are verified by the blockchain, and the immutable ledger and multi-signature on the blockchain ensures the authenticity and security of the tickets. The experimental results show that the proposed system is very efficient and requires only a nominal cost.

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49

Hsu, Bo-Chun, and 許博鈞. "Using Blockchain Smart Contract in Decentralized Application." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/bhxv77.

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Анотація:

碩士
義守大學
工業管理學系
107
Blockchain has become the most topical term due to the emergence of Bitcoin, and Bitcoin has made blockchain a technology that many experts and scholars are actively studying. The area in which blockchain can be used is not just a specific industry. Blockchains can be used in smart contracts, securities trading, e-commerce, the Internet of Things, social communications, file storage, identity verification, and the financial world. There are many revolutionized reforms in many industries driven by the Blockchain technology. In addition, the concept of decentralization also makes the information not easy to be tampered with and arbitrarily disclosed, so that the data is guaranteed. Decentralization is also a major axis of smart contracts, and the Ethereum in Ethereum must be used. Smart contracts can also be used in supply chain management, saving the company a lot of time and cost. This study uses Solidity to conduct smart contract deployment of supply management through the Rinkeby test network in the Remix environment. First, take a simple single-sales smart contract as an example to carry out the decentralized shopping smart contract deployment to the implementation process. Secondly, it is deployed and tested for the more complicated trading contract with two transit transport industries. In addition, through the Rinkeby test network, an interface platform that can interface with other platforms. The results show that smart contracts can indeed enforce contractual transactions that protect buyers and sellers under decentralized conditions.

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50

Lin, Chiu-Hung, and 林久弘. "The Study on Ethereum smart contract security." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/5cr78r.

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Дисертації з теми "Smart contact"

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